High internal phase Pickering emulsion stabilized by sea bass protein microgel particles: Food 3D printing application

Food-grade high internal phase Pickering emulsions (HIPPEs) stabilized by protein-based particles have received widespread attention because of their potential applications in the food industry. Herein, HIPPEs stabilized by sea bass protein (SBP) microgel particles were prepared using a simple one-step method. Its internal phase volume fraction was as high as 88% oil-in-water emulsion. The impact of SBP microgel particles concentration on the physical and chemical properties of HIPPEs was investigated. The SBP microgel particles improved the environmental stability of HIPPEs. Confocal laser scanning microscope (CLSM) and cryo-scanning electron microscope (cryo-SEM) images showed a three-dimensional network structure formed around oil droplets through SBP microgel particles. The average particles size of the HIPPEs droplets decreased with the increased concentration of SBP microgel particles. In rheological analysis, as the concentration of SBP microgel particles increased, HIPPEs showed higher viscoelasticity, excellent recovery, and thixotropy, which further proved the potential application of HIPPEs in 3D printing. The physical and chemical stability of astaxanthin was improved after encapsulation of HIPPEs. Further, the lipolysis degree of HIPPEs and the bioaccessibility of astaxanthin during in vitro digestion were improved also by the SBP microgel particles. Interestingly, the bioaccessibility of astaxanthin in HIPPEs stabilized by 4 wt% SBP microgel particles reached 51.17%. Three-dimensional (3D) printing experiments confirmed the extrudability, printing performance, and self-supporting properties of HIPPEs. In short, the HIPPEs stabilized by SBP microgel particles could be used as a delivery vehicle for astaxanthin, and the HIPPEs loaded with astaxanthin might have potential as a 3D printing material for edible functional foods.